lavc: set AVFrame pkt_pts and reordered_opaque in reget_buffer

Signed-off-by: Anton Khirnov <anton@khirnov.net>

libavcodec/utils.c

@@ -762,8 +762,11 @@ int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame)
     if (!frame->data[0])
         return ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF);
 
-    if (av_frame_is_writable(frame))
+    if (av_frame_is_writable(frame)) {
+        frame->pkt_pts = avctx->internal->pkt ? avctx->internal->pkt->pts : AV_NOPTS_VALUE;
+        frame->reordered_opaque = avctx->reordered_opaque;
         return 0;
+    }
 
     av_frame_move_ref(&tmp, frame);